BLOOD COMPATIBILITY OF SPUTTER-DEPOSITED ALUMINA FILMS

The surface modification of metals by the application of blood compati ble ceramics is one approach to developing durable and blood-compatibl e materials. The blood compatibility of sputter-deposited alumina film s was investigated in vitro. The alumina films were prepared by reacti ve sputtering and conventional sputtering. Diffractometer studies of t he alumina films indicate that the sputter-deposited alumina films hav e amorphous structures. Electron spectroscopy chemical analysis studie s of the alumina films indicate that the sputter-deposited alumina fil ms are nonstoichiometric (O/Al ratio of 1.15-1.66). We examined the pl atelet reaction to the alumina films and the intrinsic coagulation fac tor XII activation by the alumina films. Medical grade segmented polyu rethane was also tested. The alumina films experienced an adhesion of about 50% fewer platelets than the segmented polyurethane. Also, fewer platelet morphologic changes were observed on the alumina films than on the segmented polyurethane. Factor XII activation was less on the a lumina films than on the segmented polyurethane. Surface modification by the sputter-deposited alumina films is promising for developing blo od-compatible and durable materials. (C) 1994 John Wiley and Sons, Inc .